Conventionally, an apparatus that irradiates a target object with radiation, detects the intensity distribution of the radiation that has passed through the target object, and obtains the radiation image of the target object has been widely used in the fields of industrial non-destructive inspection and medical diagnosis. Recently, an apparatus that captures a radiation digital image by using a radiation detection panel in which radiation enters a phosphor and light irradiated in response to the radiation is converted into electrical information by a semiconductor sensor, as disclosed in PTL 1, has been developed and can quickly obtain an output image. Especially in recent years, a radiation detection panel in which radiation comes from the semiconductor sensor side, as disclosed in PTL 2, has also been proposed to improve the image quality.
It is assumed that an impact force may occur when the apparatus is dropped or the like, or an external force may be applied to the apparatus when it is used for imaging. Design of the imaging apparatus needs to consider strength, vibration resistance, and shock resistance in order for the apparatus to operate normally and perform its radiation detection function even in such a situation. Particularly, a high pressure is sometimes applied to a housing upper surface serving as the radiation incident surface of the apparatus housing, depending on the method used to capture the radiation image. At this time, the glass substrate constituting the radiation detection panel is highly likely to be broken. If the glass substrate is broken, it becomes very difficult to capture an appropriate radiation image. Thus, satisfactory protection is required to prevent the breakage of the glass substrate. At the same time, the imaging apparatus needs to be reduced in size, thickness, and weight.
To protect the radiation detection panel, various arrangements are sometimes adopted in the radiation imaging apparatus. As in PTL 3, the housing upper surface serving as the radiation incident surface of the housing that stores the radiation detection panel is made of a displaceable material having relatively low rigidity, in order to protect the radiation detection panel. The radiation imaging apparatus sometimes has a structure in which transmission of a shock to the radiation conversion panel is prevented or the shock is moderated by allowing the shock to displace the housing upper surface in a space provided between the housing upper surface and the radiation detection panel.
To protect the radiation detection panel while reducing the thickness of the imaging apparatus, the imaging apparatus may be given a structure in which the radiation detection panel is directly adhered to the housing upper surface serving as a surface on the radiation incident side inside the housing covering the radiation detection panel. The imaging apparatus sometimes has a structure that omits the highly rigid base such as is normally used, supports the radiation detection panel, and is arranged in the housing (PTL 4 or PTL 5). Again, when the radiation detection panel is adhered to the housing upper surface in the same way, the imaging apparatus sometimes may be given a structure in which a member lower in bending rigidity than the housing is used for the base, to protect the radiation detection panel and other members inside the imaging apparatus while reducing the thickness and weight of the overall imaging apparatus (PTL 6).
In addition, the imaging apparatus sometimes is provided with a buffer material that hardly appears as an artifact in a radiation image, arranged between the radiation detection panel and the housing, in order to protect the radiation detection panel from an impact force or the like from the outside of the imaging apparatus (PTL 7).